From a kayfabe standpoint, the fact Ambrose beat Corbin clean in 10M makes sense. Corbin has no chance unless he cheats to win and honestly he isn't booked as a strong enough competitor that Ambrose can't beat him. He doesn't have AJ's experience and heel knowledge to come out with a win, he isn't Reigns strong, he's inexperienced who thinks he's the best and since he didn't cheat here, he didn't win. Makes sense.
Corbin will get the belt from Ambrose at the next ppv after cheating like Styles did to get the WWE Championship off him.